CN1036485C

CN1036485C - Improved mechanical end face seal

Info

Publication number: CN1036485C
Application number: CN 93117742
Authority: CN
Inventors: J·R·瓦泽; J·P·内策尔; D·J·沃尔登
Original assignee: John Crane Inc
Current assignee: John Crane Inc
Priority date: 1992-09-18
Filing date: 1993-09-15
Publication date: 1997-11-19
Anticipated expiration: 2013-09-15
Also published as: DE69322829T2; MX9304995A; TW253018B; EP0592113B1; AU4444493A; CA2097367A1; BR9303430A; EP0592113A1; DE69322829D1; AU667384B2; CN1085636A; US5713576A; CA2097367C; ZA933894B; JPH074528A; US5375853B1; ATE175260T1; KR940007405A; US5375853A

Abstract

A double, back to back oriented mechanical end face seal arrangement for use in sealing pumps or other devices used in fluid transfer of toxic or corrosive fluid has an intermediate buffer fluid chamber into which a relatively inert gas, is provided for use as a buffer fluid. Each seal has a primary ring and a mating ring with gap maintaining means, such as spiral pumping grooves, formed in one of the rings which are shaped and dimensioned to pump the buffer gas through the first seal from the intermediate chamber into the process fluid chamber against the process fluid pressure and through the second seal from the intermediate chamber into the environment external to the housing and sealing area, thus avoiding the escape of the process fluid into the intermediate buffer chamber and thereby to the atmosphere.

Description

A kind of improved mechanical end face seal and method thereof

Generally speaking, the present invention relates to a kind of mechanical end face seal and method thereof, particularly relates to be used to seal double end-face mechanical sealing device poisonous or corrosive fluid and method thereof.

Mechanical end face seal is used to seal axle box very early and passes the space between the axle of relatively rotating of this axle box.This class seal arrangement generally includes a main ring, and this ring generally has the radial sealing surfaces on a plane, and is mounted and fixed in the axle box.This main ring can be installed on the axle box by a secondary sealer (as the O RunddichtringO).In addition, the sealing device comprises that also cooperates a ring, is installed in axle and goes up and rotate thereupon.Identical with main ring, cooperate ring that a radial seal surface that is generally the plane is also arranged.Cooperate the radial seal surface of ring in a confronting relationship, and these two radial surfaces are subjected to the bias force effect and are sealing engagement with the main ring layout.Such seal arrangement is introduced in No. 4,212,475, U.S. Patent No. that CCID (JSedy) announces to some extent, and has transferred as same assignee of the present invention.

Well-known structure is existing a lot, no matter is to use an independent seal arrangement, or in special application a plurality of mechanical end face seals are used together.For most seal applications, comprise similar devices such as pump, compressor, stirrer.When sealing the fluid of environmental sound, use independent seal arrangement just enough.But the strict day by day recently relevant pollution and the requirement of noxious emission have formed regulations, appeal " zero-emission " of poisonous fluid to environment.Like this, just propose to need the seal arrangement that can solve poisonous fluid emission problem at the sealing industry field.Near or the now existing people of some possible solutions that satisfies the zero-emission standard proposed.These schemes are divided into two big classes on Seal Design, a kind of is " wet type " binary seal arrangement, and another kind is the magnetic force driving pump form.

An example of " wet type " seal arrangement can find in No. 4,290,611, the U.S. Patent No. of awarding to CCID (JSedy), and it has also transferred commonly-assigned us of the present invention.This patent introduced " binary sealing " and installed and provided diagram (as shown in Figure 1), and this device is to have utilized two to lean against the mechanical end face seal of arranging privately along transmission shaft.These two seal arrangements form a cavity between it, have lubricated buffer fluid to circulate continuously in the cavity, are used for seal ring is cooled off.The pressure of this buffer fluid (normally oil) is generally than the high 0.34-1.36 barometric pressure (5-20 pound/inch of pressure of the process fluid that is sealed ²).It is introduced that this seal arrangement it would be desirable the seal erosion fluid,, and the metal parts of seal arrangement and process fluid have been isolated because adopted non-corrosive buffer fluid.

4,290, No. 611 described seal arrangements of patent using effect in some specific occasion is good, though can not to be used in the process fluid that is sealed be gas or be liquid but do not allow and be cushioned the occasion that fluid pollutes for it.In general, oil is the buffer fluid of using always, but many process flow physical efficiencys and oil reacts, or does not wish to suffer the pollution of oil in the process fluid.

U.S. Pat-4,212 discloses for No. 475 a kind ofly from the centering spiral groove end sealer, and it is provided with many spiral chutes on sealing surface, but does not also solve foregoing problems.

Recently, magnetic force driving pump is developed, and it has the ability of " zero-emission ", but very expensive.For such application, axle only terminates in axle box wall place and does not penetrate axle box, has so just cancelled the opening that axle is therefrom passed.The impeller of pumping fluid is enclosed in the chamber of axle box, and is connected with first group of magnet.Impeller is driven by the second group of magnet that is arranged in outside the chamber.The magnet that is arranged in the outside rotates under the effect of an external motor, and then makes the magnet face that links to each other with the impeller rotation that is enclosed in the axle box chamber.Because axle box is a complete closed, and does not have axis hole, the situation of leaking so under normal operating conditions, can not take place fluid to see through axle box.

Compare magnetic force driving pump more complicated and costliness with traditional mechanical end face seal.The magnet of transmission impeller needs special structure and special bearing, so that the impeller shaft of magnet and connection impeller keeps being straight line.In addition, magnetic force driving pump needs cooling liquid stream and takes away the used heat that changes and rub and produced owing to magnetic.

Therefore, the object of the present invention is to provide a kind of cheap, simple in structure and have " zero-emission " ability and for satisfying the seal arrangement and the method thereof of normalized day by day environment, for using generally speaking to the regulations of rules of poisonous fluid discharging.

The process fluid that prevents to be in the axle box under the pressure according to the present invention sees through the seal arrangement that the axle box wall leaks along running shaft, and above-mentioned seal arrangement comprises:

Close envelope of one first rotating machinery end body, the sealing body comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, described each ring all has radial surface, they comprise an annular, are generally the sealing surface of circumferentially extending, separate with the remaining surface of described radial surface, and being the sealing relationship that relatively rotates, cooperatively interacts with another face of described seal ring, in the described seal ring one can another moves axially relatively;

The relatively turnable seal ring of the described first end face seal body have first circumference of a described sealing surface to be exposed in the process fluid that is sealed in the axle box, and second circumference of a described sealing surface is exposed in the described intermediate cavity;

Include many spiral chutes on the sagittal plane of one of described seal ring of the described first rotating machinery end face seal body, the described circumference in the relative inertness gas extends towards the described circumferential section ground in the process fluid that is exposed to described axle box inside these spiral chutes in the described intermediate cavity from being exposed to, and the described circumference in the described process fluid is formed with a ring dam in the described axle box near being exposed on described;

It is characterized in that above-mentioned seal arrangement also comprises:

One second rotating machinery end face seal body sealing body comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, described each ring all has an annular, is generally the sealing surface of circumferentially extending, be the sealing relationship that relatively rotates, cooperatively interacts with another face of described seal ring, one in the described seal ring can move axially with respect to another, and is not subjected to the control of the moved axially seal ring of the described first rotating machinery end face seal body;

The described first and second rotating machinery end face seal bodies along axle in the axial direction at a distance of a segment distance, and constitute an intermediate cavity betwixt with described axle box, described each seal all has spring to make can to move axially separately seal ring to the biasing of respective fixation seal ring, moves axially the annular sealing surface of seal ring and the annular sealing surface of described fixing seal ring is described sealing relationship in relative rotation to keep described;

The relatively turnable seal ring of the described second end face seal body has first circumference of a described sealing surface to be exposed in the described intermediate cavity, and second circumference of a described sealing surface is exposed in the outer external environment of described axle box;

Described intermediate cavity includes the device that connects the relative inertness gas source, and the pressure of this inert gas will be stated the pressure of process fluid above the described circumference place of the described sealing surface that is exposed to process fluid;

The described first rotating machinery end face seal body also comprises one first auxiliary sealing device, it is between one of described seal ring and axle box, be used for sealing between them, with one second auxiliary sealing device, it is between another and axle of described seal ring, be used for sealing between them, described first and second auxiliary sealing devices define the border between described intermediate cavity and the described process flow body cavity separately, the radial width on the radial wall that is limited to described other radial surface is arranged and be positioned to first and second auxiliary sealing devices of the described first rotating machinery end face seal body, make and on roughly the same radius, present the basic area that equates, thereby onesize basically buffer solution pressure is acted on described other radial surface of each described seal ring of the described first rotating machinery end face seal body, and in an opposite direction, in process fluid side, identical process fluid pressure acts on the opposite side of a part of described each seal ring of the described first rotating machinery end face seal body, has eliminated the thrust that acts on the described first rotating machinery end face seal body basically.

The encapsulating method that the running shaft that the axle box wall is passed on the process fluid edge that prevents to be in the axle box under the pressure according to the present invention leaks is characterized in that this method comprises:

One first rotating machinery end face seal body is provided, it comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, one of above-mentioned two seal rings can move axially with respect to the axle or the axle box that link with it, described each seal ring all has the corresponding sealing surface of the sealing surface that is generally circumferentially extending of an annular and described another seal ring to be to relatively rotate, the sealing relationship that cooperatively interacts, so that between them, form a seal interface, each described seal ring has the rear surface that is generally circumferentially extending of annular, it is axially spaced apart with described circumferentially extending sealing surface, the described first rotating machinery end face seal body also comprise one for O RunddichtringO that described sealing relationship is provided between fixing seal ring and the axle box and one for the O RunddichtringO of described sealing relationship is provided between rotating seal ring and the axle, so that the described sealing relationship between them to be provided, the O RunddichtringO that described and described axle moveable sealing links mutually be placed in one with the adjoining of the circumferentially extending wall of one of described and axle box axial restraint.

One second rotating machinery end face seal body is provided, it comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, described each seal ring all has the sealing surface that is generally circumferentially extending of an annular and the respective face of described another seal ring to be the sealing relationship that relatively rotates, cooperatively interacts, to constitute an intermediate cavity;

Introduce relative inertness gas by a passage that is fluid communication with the relative inertness gas source in described intermediate cavity, the described circumference that the pressure that is in the described relative inertness gas in the described intermediate cavity will surpass the described annular sealing surface of the described first rotating machinery end face sealing ring is exposed to the pressure of process fluid wherein;

In axle rotation, when occurring, operate the described first rotating machinery end face seal body as the described pressure of the described relative inertness gas of the non-contact sealing of gas lubrication, disappearing substantially is coated with the thrust that acts on the described first rotating machinery end face seal body.

The O RunddichtringO of the described first rotating machinery end face seal body defines the boundary between described intermediate cavity and the described axle box, thereby makes because hydrodynamic pressure will be described moves axially seal ring presses to the end thrust that described another seal ring produces and equal at least owing to hydrodynamic pressure described another seal ring to be pressed to the described end thrust that seal ring produces that moves axially.

On the sagittal plane of one of described seal ring of the described first rotating machinery end face seal body, be provided with a plurality of spiral chutes, the described circumference of their relative inertness gas from be exposed to described intermediate cavity extends towards the described circumferential section ground of the process fluid that is exposed to described axle box inside, on described, form one near the ring dam that is exposed to the described circumference of described process fluid in the described axle box, thereby make described relative inertness gas from of described the relatively rotating of described intermediate cavity by the described first rotating machinery end face seal body, the sealing surface that cooperatively interacts is pumped to described axle box.

Introduce the present invention in detail below in conjunction with accompanying drawing.In the accompanying drawing:

Fig. 1 adopts the axle box of the preferred embodiment of the present invention and the longitudinal section of axle;

Fig. 2 is the end view of a seal ring of the preferred embodiment of the present invention; With

Fig. 3 is the end view of another seal ring of the preferred embodiment of the present invention.

Fig. 1 show one generally with 10 expressions, on the structure with the corresponding to seal arrangement of the preferred embodiments of the present invention.The sealing Design of device is the poisonous fluid that will seal in the axle box 12, so that " zero-emission " of the poisonous process fluid that certain realization is sealed definitely do not have process fluid to escape in the outer external environment of axle box.Axle box includes an axis hole 14, can make axle 16 pass axle box 12.Axle box 12 can comprise a stuffing box, and for example past attempts filling filler is used, and filler is pressed leans against axle upward to reduce the minimum level that leaks to by interface between axle box and the axle.In addition, axle box 12 also will contain the outer external environment 20 of the inner chamber 18 of process fluid and the axle box that is made of atmosphere usually and separate.

The seal arrangement of this preferred embodiment is arranged near axle box 12 and is positioned at the stuffing box that axle box 12 is constituted substantially.Seal arrangement comprise binary, the back of the body is towards the mechanical end face seal body back of the body, axially spaced-apart rotation, spiral groove type, each seal all has ring-shaped member in opposite directions, is used for being separately fixed on axle box 12 and the axle 16.The sealing device is gone up all with the type of No. 4,212,475, above-mentioned U. S. Patent similar in many aspects.

Seal arrangement generally comprise by 22 expressions, near process flow body cavitys 18 and be second seal 24 of the external environment 20 outside first seal that wall surrounded of axle box 12 and close seal arrangement and the axle box.First and second seals 22 and 24 have constituted an intermediate cavity 26 betwixt.Around intermediate cavity 26 be a bush assembly 28, this bush assembly 28 constitutes the other end of intermediate cavity 26 with flanged gland retainer plate 30.Axle 16 comprises the sleeve assembly 32 that is surrounded on axle, and it is a base apparatus, seal ring be installed in this above base apparatus and seal 22,24 around its layout.

First seal 22 comprises a pair of by a rotary seal ring 36 and the circular seal ring that fixing seal ring 40 is formed.Rotary seal ring 36 has a face 38 that radially extends, and a shoulder 37 that radially extends is arranged on excircle.Rotary seal ring 36 and fixing seal ring 40 positioned opposite, fixing seal ring 40 have a radially face 42 of extension relative with the face 38 of rotary seal ring 36.Fixing seal ring 40 is also referred to as at this and cooperates ring 40, and rotary seal ring 36 is also referred to as main ring 36 at this.As described below, this relation is not to realize the structure of the unique possible seal ring of the present invention.Main ring 36 shown in the preferred embodiment is fixed on the axle 16 and thereupon and rotates.Main ring 36 seals with respect to axle sleeve 32, but its shape and size make it that degrees of freedom of axial motion be arranged at least to a certain extent with respect to axle sleeve 32 and axle 16.

As shown in Figure 1, main ring 36 is fixed on sense of rotation with respect to sleeve assembly 32, so that rotate thereupon.But in other embodiment's (not shown), main ring is fixed with respect to axle box, also is possible and cooperate ring to rotate with axle.In this embodiment, need perhaps that those skilled in the art carry out proper arrangement and improvement to this device in related domain, just can finish this alternate design.

Cooperate ring 40 that face 38 face 42 in face-to-face relationship with main ring 36 is arranged.When they were close together, face 38 and 42 formed butt joint, and the sealing function of seal 22 is provided.This interface does not need and face 38 and 42 equal sizes, and as shown in Figure 1,38 in the face of main ring 36 has covered a part that cooperates the face 42 of ring 40.

Interface between the face 38 and 42 is annular disk-shaped, and axle 16 center holes from each ring pass.As shown in Figure 2, cooperate on the ring 40 and include many spiral chutes 44, occupied the part of 40 the face 42 of encircling, by circumferential its internal diameter circumferential extension of external diameter.Groove 44 is also shown in broken lines in Fig. 1, but for the ease of expression, the degree of depth of groove is by exaggerative.Described according to No. 4,212,475, above-mentioned U. S. Patent, the degree of depth of groove is in the order magnitude range of 1.27～10.16 μ m (50 to about 400 inches).The about 7.62 μ m of groove depth (300 inches) in this preferred embodiment.

See also Fig. 2, groove 44 is separated between homogeneous phase and by many terrace with edges 45 that radially extend in a circumferential direction.The surface of sealing surface 42 inner radius unslotteds has constituted sealing dam 46, when axle 16 does not rotate, it provides static sealing together with the face 38 of relative main seal ring 36, and when axle 16 did not rotate, process fluid was by main ring and cooperate hydrostatic film between the ring in the sealing of sealing 46 places, dam.When axle 16 began to rotate, the face 38 of groove 44 and the ring 36 that the rotates fluids that will be present in usually in the chamber 26 that interact radially inwardly pumped into through sealing surface 38,42, sealing surface is opened slightly, thereby form a slit between face and face.The fluid that is drawn into the slit makes and keeps contactless state between the sealing surface, and this face is cooled off, and then prevents that generation is overheated under the effect of the caused tangent direction friction power of the relative rotation of sealing surface.

Cooperating on the ring 40 the other end (Fig. 1) opposite with face 42, a depression or a thorax hole 41 that holds locating stud 43 is arranged, this pin 43 makes ring 40 fix with respect to bush assembly 28 and axle box 12.Locating stud 43 generally is parts of bush assembly 28, and can be processed into whole parts as the part of this assembly.But locating stud 43 is independent parts preferably.Its during fabrication depended on pressure be assembled in the lining.Cooperating the sealing between ring 40 and the bush assembly 28 to be to use seal ring 47.Cooperating the shoulder that encircles on 40 outer circle walls to form the annular wall 39 of a circumferentially extending, annular wall 39 corresponding circumferentially extending wall on bush assembly abuts against.

Shown seal 22 is having groove 44 near the radially outer diameter place of intermediate cavity 26, and near and be exposed to that there is the dam 46 of sealing at the radially inner diameter place in the process fluid in the chamber 18 in.But principle of the present invention is equally applicable to groove in inner radius, the dam situation in outer radius, and the groove of inner radius is exposed to the seal in the buffer fluid in the intermediate cavity.This another embodiment's (not shown) may need the different ring of a kind of structure, for example cooperates the ring rotation and main ring is fixed.On the basis of understanding characteristics of the present invention, the professional and technical personnel can design other alternative structure.

Sleeve assembly 32 comprises an axle sleeve 48 that is contained on the axle 16.Axle sleeve 48 includes a thicker part 50 at the one end, in the then recessed formation one thin part 51 of another annular end of axle sleeve 48.Axle sleeve 48 is fixed on the axle 16 by the axle collar 52, and the axle collar 52, also will go on to say below this point to the thin portion 51 of axle sleeve 48 by bolt.Also can adopt the structure (not shown) of driving key that axle sleeve 48 is fixed on the axle 16 in addition.Sleeve assembly 32 comprises that also one is used for seal ring 56 that thick portion 50 and axle are sealed between 16 and another and is used for the seal ring 58 that seals between main ring 36 and the thick portion 50.Axle sleeve 48 recessed thin portions 51 are suitable for the other parts of fitting tight device, for example parts of second seal 24.

O RunddichtringO 56 and 58 is installed in the thick portion 50 in the corresponding groove, and the seal ring on the external diameter 58 is made on shape, size and structure and allows main ring 36 that axial motion is arranged.The diameter of seal ring 58 is as much as possible near the diameter of seal ring 47.The seal ring of same diameter is strengthened the sealing harmony of seal 22, because it can make the power that pressure produced because of being present in the process fluid in the chamber 18 be tending towards equal.Seal ring has been determined the position diametrically, border between buffer fluid pressure and the process fluid pressure, also will go on to say below this point.Seal ring 47,58 can make the pressure balance that acts on the seal ring 36 and 40 radially extensional surface separately like this.When the higher buffer fluid of pressure acts on the wall 39 that seal ring 40 radially extends, the same but opposite power of direction will act on the face of seal ring 36, and this face is the other end opposite with face 38 on seal ring 36.Because the width at the non-contact sagittal plane that is close to the identical annular density of radius upper wall 39 on diametric(al) and ring 36 embodies the basic area that equates, so that buffer fluid acts on size of each ring upward pressure is also equal substantially.Although its direction is opposite.In process fluid one side, act on and cooperate the pressure of the process fluid on ring 40 parts and the relative both sides of main ring 36 parts also to equate.Like this, the pressure that acts on each ring is cancelled out each other, and has therefore eliminated the thrust that acts on the seal 22 basically.

Seal 24 also comprises a pair of circular seal ring.A ring is made of the retaining ring 60 with sagittal plane 62.Relative with fixing seal ring 60 is swivel becket 64, and it also has a sagittal plane 66 relative with the face 62 of retaining ring 60.The fixing seal ring 60 of second seal 24 is also referred to as fitted seal ring 60, and swivel becket 64 is also referred to as main seal ring 64.

Main seal ring 64 is structurally different with main ring 36.For example an end opposite with seal face 66 has a groove on the main seal ring, is used to install seal ring 70, seals between the thick portion 50 of 70 pairs of rings 64 of seal ring and axle sleeve 48.In many aspects, comprise the configuration of seal ring 70, second seal 24 all is similar with 4,212, No. 475 described seal arrangements of above-mentioned U. S. Patent.But, one very important aspect, seal 36 is different with the like of the described seal arrangement of this patent.4,212, the main ring described in 475 patents at a stop sheath internal fixation on axle box.But in a preferred embodiment of the invention, main ring 64 rotates, and cooperates ring 60 to fix.Different design philosophys is applicable to any occasion.For example, the stop sheath of seal arrangement comprises the inner diameter wall of a prolongation in this patent, and a seal ring that relies on sealing main ring is arranged thereon; And in the present invention, corresponding 70 of seal rings are installed on the axle sleeve 48.Yet content disclosed by the invention is applicable to any sealing configuration that can design in this professional basic fundamental scope.

Please consult shown in Figure 1ly again, the shoulder on main ring 64 outer circle walls provides a radially ring wall 72.

The cooperation ring 60 of seal 24 is also different with cooperation ring 40.Cooperating ring 60 is annulus, and the usefulness of circular groove 77 for the seal ring 75 of packing into is arranged on its outer circle wall.Seal ring 75 is used to cooperate the sealing of 30 of ring 60 and gland retainer plates.

Seeing also Fig. 3, is the front view of the sealing surface 62 of ring 60 shown in the figure, and sealing surface 62 also comprises one group at the spiral chute 74 that makes progress in week separately.The length of groove just cooperates the part of ring sealing surface 62 radial width, and also expresses on the cooperation ring 60 in Fig. 1, just for the ease of diagram width has been exaggerated.The surface of sealing surface 62 inner radius unslotteds constitutes a sealing dam 76, and is similar with the sealing dam 46 of seal 22, and it provides a static sealing together with the sealing surface 66 of relative main ring 64 when axle 16 does not rotate.When axle rotated, the buffer fluids in the intermediate cavity 26 are extracted and entered to axle 16 and the rotation of main ring 64 relative engagement rings 60, and the interaction of spiral chute 74 on the surface of revolution 66 of main ring 64 and the sealing surface 62 out external environment 20 through the seal interface of seal 24.

Adopting secure fit ring 40,60, and include the end face 42,62 of spiral chute 44,74 respectively, is opposite part with the design of most of seal arrangements.But have been found that it no matter is that seal arrangement described in No. 4,212,475, the U. S. Patent is arranged in spiral chute on the rotating ring like that as described above, still as make the spiral chute maintenance static among the present invention, getting on the amount of fluid and the direction at pump does not all have significant difference.

Can believe that fluid film is attached on the rotating ring, although its surface is more smooth, smooth, although and on rotating ring, do not have a volute pump bothrium.Fluid film is attached to level and smooth sealing surfaces and is that the rotation of the end face 42,62 of ring 40,60 makes stationary fluid mobile relatively with the phenomenon of its rotation, produces the result of laminar flow effect.Because fluid film has run into the face 42,62 that cooperates ring 40,60, be forced in each face 42,62 upper edge surface boundary layers and radially inwardly flow so fluid film is subjected to the constraint of groove 44,76.Though there have the spiral fluted environmental protection to hold to be static, in the counterrotating process, the laminar flow effect is enough to pump into enough fluids between face and face between face and face, and forms a slit between face and face.

In order to offset the increase tendency in the formed slit of fluid, need a bias force.If it is excessive that the slit becomes, the leakage of the higher side of fluid selfsealings body pressure just need be controlled excessive.See also Fig. 1 again, by one group of a plurality of spring 80 arranging equably around the circumference of circular main ring 36,64, apply a bias force separately to main ring 36,64, spring 80 directly is pressed in respectively respectively on the pair of discs 82,84 near an end face separately of main ring 36,64, and this end face lays respectively at an end opposite with sealing surface 42,62.Like this, the power of spring 80 will be offset spiral fluted and open power, and acting on the pressure of ring 36,64 on separately simultaneously will cancel out each other.

Spring 80 is by stop sheath 90 location with a cylindric excircle 92.Stop sheath 90 has an inwall that prolongs and has formed an annulus, holds the cooperation ring 40 of seal 22 at its end, and its other end holds the cooperation ring 60 of seal 24.

Core in inner diameter wall 94 is a disc-shaped part 96.In a preferred embodiment, disc 96 is made one with stop sheath 90.Include many extended from it through holes 94 on the disc 96.The diameter of through hole 94 is even as big as inserting spring 80 wherein.Stop sheath 90 and disc 96 can make spring 80 in circumferential and radial location like this.Spring 80 is arranged along between the circumference homogeneous phase of disc 96, provides uniform bias force on the whole circumference that cooperates ring 40,60, acts on to cooperate on the ring 40,60.In a preferred embodiment, have 4 springs, on disc, arrange at interval by 90 °.

The internal diameter of stop sheath 90 at disc 96 places is the thick portion 50 near axle sleeve 48.The hole that separates with axial hole 94 that a plurality of headless screw (not shown) radially pass radial arrangement on the disc.This headless screw is pressed on the outer surface of axle sleeve, so stop sheath 90 is fixing on axial and circumferential with respect to axle sleeve 48.Like this, in the operation process of the equipment that adopts this seal arrangement, stop sheath 90, disc 96, main ring 36,64 and spring 80 are all along with axle 16 rotates together.

Near the two ends part inside groove 98 is arranged respectively also on the internal diameter of cylindric stop sheath 90, be used to hold snap ring 100.Each snap ring 100 is contained within the groove 98 and a wall 102 that radially extends is provided.The wall 102 of a snap ring 100 docks with the wall 37 of main ring 36, should encircle retaining within stop sheath 90.Equally, the wall 102 of another snap ring 100 docks with the radial wall 72 of main ring 64, so that T-Ring is kept off within stop sheath 90.But under normal operational condition, each main ring is all through giving loading, so the corresponding wall 37,72 of each main ring separates with snap ring wall 102 in assembling process.

Said, bush assembly 28 is installed within the Stuffing box that wall 12 constitutes and has encased the part of sealing device, includes the part of seal 22 and retaining assembly 90.Bush assembly 28 includes an internal diameter ring-type supporting lip part 110, constitutes to hold the cooperation ring 40 of seal 22 around its internal diameter.The radially wall extension 39 of main ring 36 abuts against on the corresponding radial wall of flange portion 110.

Flange portion 110 also includes a plurality of axial pin holes 112, is used to hold pin 43, so that be maintained fixed joint between flange 110 and the cooperation ring 40.Circular groove 114 provides a seal space that holds seal ring 47, seals between 47 pairs of bush assemblies 28 of seal ring and the main ring 36.

The external diameter flange portion 120 of bush assembly 28 is bound up with internal diameter supporting lip part 110 by a tubular portion that prolongs 116.The external diameter of tubular portion 116 is installed within the axle box wall 12, but need not seal with it.The sealing that prevents escape of liquid between bush assembly 28 and the axle box 12 is finished by seal ring 122, and seal ring 122 is installed within the groove 124 in external diameter bight between external diameter flange portion 120 and the tubular portion 116.Groove 124 is identical with the external diameter of tubular portion 116 at the diameter that one extends axially the wall place, so can think that it is the extension of tubular portion 116 outer walls.In this position, when the radially wall extension 126 of outer flange portions 120 was close on the wall of axle box 12,122 of seal rings were pressed against on the axle box wall, so that form sealing between bush assembly 28 and the axle box 12.Seal load be in axial be in than it radially more favourable because by tubular portion is slided with respect to Stuffing box, mounting bush more easily.

Outer flange portions 120 preferably comprises a coupling gear that links to each other with the wall of axle box 12, also will continue below this point to introduce.One group of deep hole 128 that several bolts 130 (shown in dotted line) are passed in equidistant layout on the radial wall of outward flange 120 extends (shown in dotted line), and bush assembly 28 and flanged gland retainer plate 30 are tied.

Gland retainer plate 30 includes an inner-diameter portion whose, and this inner-diameter portion whose has axially extended internal diameter sealing surfaces 132, and seal ring 75 is pressed and sealed thereon.Groove 77 is arranged on the excircle diameter that cooperates ring 60, and its degree of depth has enough allowances that cooperation ring 60 can be packed under pressure by in the 132 formed annular shoulders of surface.With seal ring 75, can realize cooperating the seal action that prevents escape of liquid between ring 60 and the gland retainer plate 30 effectively.

Gland retainer plate 30 comprises that an inlet 134 is connected intermediate cavity 26 with one and 134 the fluid passage 136 of entering the mouth.Inlet 134 itself be linked in a gas source and with its maintenance fluid communication, this gas response environment harmless and with the use of special process fluid be compatible.Any relative inertness gas, or with the gas that process fluid does not react, all can be used as buffer gas and use.Nitrogen is a kind of preferred relative inertness gas owing to cost is low with obtaining easily, but other rare inert gas also can consider to be applicable to the specific occasion as argon gas, neon or other similar gas.In some other limited several applications, be compatible if use air and process fluid, so also available it as buffer fluid.

In addition, in some specific application, the gas that reacts with process fluid also is operable, is desirable in this this reaction, for example when adding in the sort buffer gas in some stage of treatment process fluid.For example, adding carbon dioxide in process fluid may be as process fluid being carried out a chemically treated part and implementing.When adopting this mode, importantly the buffer stream scale of construction that is input in the process fluid is accurately measured, pump into the buffer stream scale of construction in the process fluid but also need to calculate, desirable chemical reaction takes place and required amount of carbon dioxide so that only provide by spiral chute.

In suitable environment, the pressure of buffer gas is the maximum pressure that surpasses the process fluid expection.Best-case is (10 pounds/inch in high 0.68 barometric pressure of maximum pressure of the pressure ratio process fluid that the nitrogen that source nitrogen provides to inlet 134 flows ²).Source nitrogen can be any in several possibility modes.For example, if be used for a chemical plant, then source nitrogen can be a built-in pipeline, and nitrogen can be the by-product that different chemical is handled, and this is ready-made in most of chemical plant.The nitrogen pressure that offers inlet can be adjusted to desired level between source nitrogen and inlet.

In addition, source of the gas can be a high-pressure nitrogen bottle, and it also needs a controlling device that institute is transferred to expecting pressure for nitrogen.In a preferred embodiment, approaching in order to be easy to, inlet is arranged on the peak of gland retainer plate 30, and with regard to operation, this not necessarily, and in other structure, in order to adapt to special applicable cases, may need to provide inlet with diverse location and different orientation angle.

The axle collar 52 is in axially directly being arranged in outside the seal arrangement, and the connection between axle sleeve 32 and the axle 16 is provided.With regard to but the parts for axial motion in each seal provided the activity allowance, the axial position of axle sleeve 32 was very important.For the location-appropriate that guarantees that axle sleeve is arranged in the axial direction, the axle collar 52 has been installed, and the headless screw shown in the with dashed lines 140 is tied on axle sleeve 32.Headless screw 140 sees through axle sleeve 32 and penetrates in the axial bore 140 predetermined on the axle 16, thus three parts is bound up and it is axially interfixed.

By using several position shelfs 144, can make between axle sleeve 32 other parts to have suitable spacing with respect to gland retainer plate 30 and seal 22,24.Position shelf 144 is right angle bendings that two limits are arranged, and connects by the tap bolt (not shown) one bar limit and the axle collar 52, and another limit and gland retainer plate 30 connect, and screw is screwed in the screw (not shown) that suitably is arranged on the axle collar 52 and the gland retainer plate 30.

Use in 144 processes on seal arrangement being assembled to axle 16 of position shelf, and remove immediately after the installation, as being represented by dotted lines among the figure.Leave the position shelf of main body.Yet, be associated in shown in Fig. 1 together, with the relation between each parts of expression seal arrangement.After finishing, assembling removes the relativeness that position shelf 144 can not change these parts.

The material that constitutes various specific features all can have been bought on market, and great majority all are the standard materials of sealing industry.In a preferred embodiment, main ring 36,64 is carbon graphite (Carbon graphite) ring, is silicon cemented carbide or tungsten Hardmetal materials and cooperate ring 40,60.Spring 80 is rustproof spring steels, and lining, gland retainer plate 30, axle sleeve 32, the axle collar 52, position shelf 144 and variously have head, headless screw all can be made by the steel that is suitable for, for example No. 316 stainless steels.

Some seal ring is exposed in the process fluid, and these fluids in most cases are corrosive or poisonous.Like this, seal ring then must be made with relative impermeabilisation or for the material of most of corrosive fluid resistances to chemical attack.Therefore, seal ring 47,56 and 58 is made by the synthetic rubber of resistance to chemical attack, for example, and the perfluoro synthetic rubber.Because the expense of these materials can not be extensive use of this seal ring in whole sealing device.Seal ring 70,75 and the normally used elastic material of 138 available separately seal rings are made, for example fluorocarbon synthetic rubber, chlorobutadiene, ethene, propylene or fine.Under the seal arrangement normal operation, seal ring 70,75 and 138 is not exposed in corrosive process fluid, does not then need to use the tartan of resistance to chemical attack or impermeabilisation like this for these seal rings.

Assembled seal 10 must be carried out according to preset program.It is at the tubular assembly that does not just assemble to the scene of using seal arrangement with main Sealing that the structure of seal arrangement 10 the bests is installed.Like this, having only of required assembling installed seal arrangement tubular assembly at the scene in this case, is attached to gland retainer plate 30 on the axle box 12 and to regulate the axial position of axle sleeve 32 just passable.

When in the manufactory at non-use scene, assembling the tubular assembly, begin earlier disk 84 to be placed in an end of stop sheath 90, again this disk is shifted onto the center disk portion 96 of stop sheath.Then seal ring 70 is packed into the annular shoulder 84 of main ring 64, the stop sheath 90 of again main ring 64 being packed into leans against on the disk 84 one side opposite with sealing surface 66.With snap ring 100 groove 98 of packing into, main ring 64 is stuck in the stop sheath 90.

Next step is the end that stop sheath 90 has thin portion 51 with main ring 64, disk 84 and seal ring 70 from axle sleeve 32 to be set on the axle sleeve 32 and to thick portion 50 advance, and engages with the external diameter of the thick portion 50 of axle sleeve until the internal diameter of internal diameter, seal ring 70 and the main ring 64 of disk 84.

Then with spring 80 from the other end of stop sheath 90 around the stop sheath center disk portion mating hole 94 of packing into, spring 80 is engaged with disk 84.Subsequently disk 82 is packed into from the other end of stop sheath 90, contact with spring 80 until this disk.Seal ring 58 is packed in the groove on axle sleeve 32 external diameters, again the other end of main ring 36 from stop sheath 90 inserted, the back side opposite with sealing surface 38 is contacted with disk 82.Must be careful when inserting main ring 36, avoid making the bight of main ring 36 internal diameters to be expressed to or to scrape on seal ring 58.

After seal ring 58 was crossed at the back side of main ring 36,82 pairs of springs 80 of main ring 36 and disk had compression to a certain degree.Second snap ring 100 is installed in the groove 98 with the first snap ring end opposite, so just two main rings 36,64 all is stuck within the stop sheath 90.Spring 80 will make main ring 36,64 outwards setover, and engage with husky ring 100 up to corresponding shoulder 72,37.

Make thick portion 50 axial alignment in main ring 36,64 spaces that limited of axle sleeve 32 then, and a plurality of headless screw (not shown) are inserted in the radial hole (not shown) of stop sheath center disk portion 96 and the thick portion of axle sleeve 50 equal intervals layout, stop sheath 90 and axle sleeve 48 are tied, and stop sheath 90 is fixed, at axial and circumferential so that rotate with axle sleeve.Seal ring 56 can be in office what easily the time marquis pack in the inside groove of axle sleeve 32.

Next be mounting bush assembly 28 and locating stud 43, locating stud has been pressed in the hole 112 of bush assembly inner-diameter portion whose 110 in manufacture process.Seal ring 47 is packed in the groove 114, will cooperate ring 40 to be inserted in the bush assembly, make to cooperate on the ring 40 another non-tight face opposite to engage, and make pin 43 be inserted into cooperation to encircle in 40 the hole 41 with the inner-diameter portion whose 110 of bush assembly with face 42.Must be careful during operation, guarantee that seal ring 47 does not hinder the insertion that cooperates ring 40.

Next installation step is toward in the circumferential groove 77 that cooperates ring 60 seal rings 75 being installed, and will cooperate ring 60 to pack in the gland retainer plate 30, makes to cooperate to encircle 60 external peripheral surface and engage with the surface 132 of gland retainer plate 30.Seal ring 138 is arranged in the groove 139 of gland retainer plate.

With stop sheath 90 and all appurtenances, comprise main ring 36,64 and axle sleeve 32 location in sleeve assembly 28 together, make to cooperate the sealing surface 42 of ring 40 to engage with the sealing surface 38 of main ring 36.Then with gland retainer plate 30 with cooperating ring 60 to be contained in the thin portion 51 of axle sleeve 32 and to front slide, engage until sealing surface 62 and 66.

Make thick portion 50 axial alignment in main ring 36,64 spaces that limited of axle sleeve 32 then, and a plurality of headless screw (not shown) are inserted in the hole (not shown) of stop sheath center disk part 96 and the thick portion of axle sleeve 50 equal intervals layout, stop sheath 90 and axle sleeve 32 are linked, and make stop sheath 90 fixing on axial and circumferential, so that rotate with axle sleeve.Seal ring 56 can be in office what pack into inside groove of axle sleeve 32 of marquis easily the time.

Between bush assembly external diameter flange portion 120 and gland retainer plate 30 obvious gaps should be arranged, this is because spring 80 is in elongation state, and main ring 36,64 is biased on the limit of snap ring 100 stop position that limits.Make the hole location of gland retainer plate 30 with respect to external diameter flange portion 120 then, make it be in straight line, so that inserting bolt 148, this bolt can be attached to this assembly on the axle box 12.Therefore gland retainer plate 330 axially is pressed into, and pressure spring 80 makes main ring 36,64 close mutually in compression.Bolt 130 is inserted and tightens, bush assembly is attached on the gland retainer plate 30, and reserve main ring 36,64 in two positions that cooperate between the ring sealing surface 42,62.But axle sleeve 32 and stop sheath 90 are can be in axial sliding with respect to the position of main ring 36,64.

When tight a bolt 130 and gland retainer plate 30 is attached on the external diameter flange portion 120 of bush assembly 28 after, seal arrangement 10 had been installed on the axle 16 in the past.At first one group of position shelf 144 is attached on the radial wall in the gland retainer plate outside apart from the suitable part of radius of central line, its method is the tap bolt (not shown) to be passed the limit that each position shelf 144 radially extends be screwed in the hole of gland retainer plate 30.Then the axle collar 52 is packed in the space that another axially extended limit limited by each position shelf 144, and position shelf 144 is fixed on the axle collar 52 with tap bolt.Seal arrangement can be transported to the erecting bed then.

Can be with a wing pump (not shown) as the suitable example that seal arrangement is installed.At first should pull down the motor (not shown) of this pump, it should be arranged in Fig. 1 right side, is bound up on the axle 16.Other material, for example old filler must take out from the stuffing box that axle box 12 is constituted; If desired, reply axle, stuffing box and wall 12 lip-deep chips and corrosion are cleared up.The seal arrangement that will be the tubular assembly carefully inserts then, the outside diameter wall of bush assembly inner-diameter portion whose 110 is packed in the stuffing box that is made of axle box 12, and simultaneously axle sleeve 32 is contained on the axle 16.Must be careful during operation, to guarantee that seal ring 56 does not hinder the slip of axle sleeve 32 on axle 15.

Then seal arrangement tubular assembly 10 is advanced along axle 16, engage with the radial wall of axle box 12 until the radial wall 125 of bush assembly external diameter flange 120, and compress seal ring 122 simultaneously with realization seal action therebetween.

Bolt 148 inserted pass in the corresponding hole of gland retainer plate 30 and bush assembly external diameter flange portion 120, and be screwed in the screw 150 on axle box 12 radial walls.Bolt 148 is fixed on the stationary part of seal arrangement tubular assembly 10 on the axle box 12, and simultaneously sleeve assembly 32, can move freely in the axial direction with stop sheath 90 main rings 36,64, and can rotate with axle.

By the position of the stop sheath 90 that links with the position of position shelf 144 fixed axle sleeve assemblies 32 with axle sleeve 48, once more sleeve assembly 32 is carried out axial alignment.Determine the position in holes 142 to make its axial position with respect to axle 16 suitable with position shelf 144, rotatingshaft 16 slightly again is positioned on the screw on the axle 16 hole 142 of the axle collar 52.Then headless screw 140 is inserted in the hole 143 of the hole 142 of the axle collars 52 and the thin portion 51 of axle sleeve, and is screwed into screw, thus fixedly the axle collar 52 and sleeve assembly 32 with respect to the position of axle 16.Back out the tap bolt (not shown) then, remove position shelf 144, make axle free to rotate with respect to axle box.

The action need user of seal arrangement 10 provides the relative inertness gas source as buffer fluid, for example nitrogen or certain rare inert gas.The pressure of the gas that provides should surpass (10 pounds/inch in maximum pressure at least 0.68 barometric pressure of process fluid ²).

The pressure of buffer gas may be more much higher than the pressure of process fluid, then needs a controlling device that pressure is reduced to desired level in this case.Buffer gas infeeds inlet 134 continuously, and gas enters intermediate cavity 26 by connecting passage 136 then.

In the rotary course of axle, the assembly of being made up of stop sheath 90, main ring 36,64 and axle sleeve 32 rotates with axle 16, rotary component and are interfaces between the corresponding separately sealing surface 38,42 and 62,66 of seal 22,24 with respect to the axle box 12 fixing unique direct contact surfaces of static part.That is, when cooperating ring sealing surface 42,62 to keep static, the face 38,66 of main ring rotates to it.

Stable buffer gas stream is provided in intermediate cavity 26, make its pressure surpass the maximum pressure of process fluid in the axle box 12, and the pressure (being generally barometric pressure) that surpasses the outer external environment of axle box, in the rotary course of axle, force buffer gas to enter and by by the formed slit of sealing surface.Like this, the unique leakage that sees through the sealing surface 38,42 of seal 22 be exactly buffer gas from the leakage of intermediate cavity 26 to axle box chamber 18, see through seal 24 sealing surface 62,66 then be by the leakage of intermediate cavity 26 to external environment, for example atmosphere 20.

Though in the rotary course of axle, avoided the actual contact between the sealing surface, be formed on also enough little in slit between the sealing surface, so that keep buffer fluid to have only very little by the leakage of seal 22,24.Interface between two groups of sealing surfaces has kept such sealability, and promptly one makes process fluid in the axle box and the sealing between the intermediate cavity, and another makes the sealing between intermediate cavity and the axle box external environment outward.

In a preferred embodiment, cooperating spiral chute 44 on the ring sealing surface 42 also buffer gas to be pumped from intermediate cavity 26 also is extracted among the process flow body cavity 18.Ideal situation is, the pump-absorb action of spiral chute 44 and the pressure of buffer gas are harmonious, keeps seeing through the direction of all leakage parts of seal 22 along expection, and prevents poisonous or corrosive process fluid is overflowed and entered in the intermediate cavity 26.In addition, even because unexpected, some process fluids leak in the intermediate cavity really, and the malleation of buffer gas on another direction also can make it turn back in the chamber 18.

The structure of this sealing system is added the buffer gas of malleation, can prevent all that in most of the cases fluid process leak is in atmosphere.Fluid process leak can be do not made if seal damages yet,, the signal that system need shut down will be provided when following when pressure drops to predetermined value because to the continuous monitoring of gas pressures in the intermediate cavity 26.For example, if one of seal 22,24 has damaged, then can occur pressure immediately immediately and descend in intermediate cavity, it will cause system to shut down and axle 16 stops operating.If what damage is seal 22, then owing to the static sealing effect on dam 76 on the sealing surface 62, system shuts down and can not cause process fluid to overflow in intermediate cavity 26.In contrast, if seal 24 has damaged, the static sealing that is provided by the dam 46 of sealing surface 42 will prevent that process fluid from entering intermediate cavity, therefore can only have buffer gas to overflow from intermediate cavity.

The advantage of seal arrangement of the present invention comprises the buffer fluid of having cancelled " wetting ", and is for example oily, and it may become dirty and may pollute process fluid.Oil lubricant is the comparison costliness in addition.

On the contrary, the preferred embodiments of the present invention are dry method running sealings, are as oiling agent with gas.When adopting spiral chute, sealing surface is separated from each other.Between face, produce a slit, and adopt the non-contact sealing means that the life-span of seal is prolonged, and reduce because the heat that contact friction produced.See through and play a kind of effect of freezing mixture, can take away the heat that viscosity shearing stress is produced between sealing surface through a spot of but stable buffer gas stream of sealing surface.With regard to not needing buffer fluid is circulated in sealing area like this, because there is not the problem that produces frictional heat.

Be used to seal under the situation of poisonous process fluid, adopting nitrogen to obtain the allowance of environmental regulations and department as a kind of buffer gas.In addition, will system be shut down when breaking down, so can under the situation that is not equipped with the gas leakage continuous monitoring of being carried out at poisonous fluid effusion, use according to seal arrangement of the present invention owing to seal.

Seal arrangement of the present invention can be used in multiple sealing occasion, comprises most pump.For example, the sealing device can be used for wing pump, its space around the case inner seal ring of can finding time immediately, thus partial vacuum is provided at least.For wing pump, nitrogen " consumption " (promptly spraying into the nitrogen amount in the axle box chamber) can reduce, because the partial vacuum that impeller caused can reduce the compensator or trimmer pressure of nitrogen.Yet, had better make to keep (10 pounds/inch in about 0.68 barometric pressure between impeller cavity and the intermediate cavity ²) pressure difference.

Though preferred form of the present invention has been done detailed description, in fact under the situation that does not exceed following claim scope, can also produce other alternative form.

Claims

1, a kind of process fluid that prevents to be in the axle box under the pressure sees through the axle box wall and the seal arrangement that leaks along running shaft, and above-mentioned seal arrangement comprises:

One first rotating machinery end face seal body, the sealing body comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, described each ring all has radial surface, they comprise an annular, are generally the sealing surface of circumferentially extending, separate with the remaining surface of described radial surface, and being the sealing relationship that relatively rotates, cooperatively interacts with another face of described seal ring, in the described seal ring one can another moves axially relatively;

Include many spiral chutes on the sagittal plane of one of described seal ring of the described first rotating machinery end face seal body, these spiral chutes extend from being exposed to the described circumferential section ground towards the process fluid that is exposed to described axle box inside of the described circumference in the relative inertness gas in the described intermediate cavity, and closely on described are exposed to that the described circumference in the described process fluid is formed with a ring dam in the described axle box;

It is characterized in that above-mentioned seal arrangement also comprises:

One second rotating machinery end face seal body, the sealing body comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, described each ring all has an annular, is generally the sealing surface of circumferentially extending, be the sealing relationship that relatively rotates, cooperatively interacts with another face of described seal ring, one in the described seal ring can move axially with respect to another, and is not subjected to the control of the moved axially seal ring of the described first rotating machinery end face seal body;

The described first rotating machinery end face seal body also comprises one first auxiliary sealing device, it is between one of described seal ring and axle box, be used for sealing between them, with one second auxiliary sealing device, it is between another and axle of described seal ring, be used for sealing between them, described first and second auxiliary sealing devices define the border between described intermediate cavity and the described process flow body cavity separately, the radial width on the radial wall that is limited to described other radial surface is arranged and be positioned to first and second auxiliary sealing devices of the described first rotating machinery end face seal body, make and on roughly the same radius, present the basic area that equates, thereby onesize basically buffer solution pressure is acted on described other radial surface of each described seal ring of the described first rotating machinery end face seal body, and in an opposite direction, in process fluid side, identical process liquid pressure acts on the opposite side of a part of described each seal ring of the described first rotating machinery end face seal body, has eliminated the thrust that acts on the described first rotating machinery end face seal body basically.

2. seal arrangement as claimed in claim 1, it is characterized in that, described first and second auxiliary sealing devices comprise an O RunddichtringO, be placed between described fixing seal ring and one of described axle box and axle with sealing relationship, with an O RunddichtringO, be placed between another of described rotating seal ring and described axle box and axle with sealing relationship.

3. seal arrangement as claimed in claim 1, it is characterized in that, described spiral chute on the sealing surface of one of described seal ring of the described first rotating machinery end face seal body extends from the internal diameter on the described seal ring of outer radial surface, and described ring dam is near the internal diameter on described seal ring surface.

4. seal arrangement as claimed in claim 1 is characterized in that, the described spiral chute on the sealing surface of one of described seal ring of the described first rotating machinery end face seal body is opened on described fixing seal ring.

5. seal arrangement as claimed in claim 2, it is characterized in that, move axially the described O RunddichtringO that seal ring links mutually and comprise a radial wall that links mutually with one of described axle and axle box with described, the axial position of described radial wall is fixed, and is placing described the adjoining of O RunddichtringO between seal ring and one of described axle and axle box that move axially with sealing relationship.

6. seal arrangement as claimed in claim 3, it is characterized in that, move axially the described O RunddichtringO that seal ring links mutually and comprise a radial wall that links mutually with one of described axle and axle box with described, the axial position of described radial wall is fixed, and is placing described the adjoining of O RunddichtringO between seal ring and one of described axle and axle box that move axially with sealing relationship.

7. seal arrangement as claimed in claim 1, it is characterized in that, the described seal ring that moves axially of the described first rotating machinery end face seal body also comprises a circumferentially extending surface that separates with described radial sealing surfaces, and described surface is exposed among the interior process fluid pressure of described axle box.

8. seal arrangement as claimed in claim 5, it is characterized in that, the described seal ring that moves axially of the described first rotating machinery end face seal body also comprises a circumferentially extending surface that separates with described radial sealing surfaces, and described surface is exposed among the interior process fluid pressure of described axle box.

9. seal arrangement as claimed in claim 6, it is characterized in that, the described seal ring that moves axially of the described first rotating machinery end face seal body also comprises a circumferentially extending surface that separates with described radial sealing surfaces, and described surface is exposed among the interior process fluid pressure of described axle box.

10. seal arrangement as claimed in claim 1 is characterized in that, described relative inertness gas is taken from following one group of gas: nitrogen, carbon dioxide, air and a kind of rare inert gas.

11. seal arrangement as claimed in claim 1 is characterized in that, described first and second Sealings comprise a tubular modular construction.

12. seal arrangement as claimed in claim 1, it is characterized in that, it also comprises an axle sleeve that is connected with described axle hermetically, described axle sleeve is placed in described axle and described first the described of rotating machinery end face seal body moves axially between the seal ring, the described seal ring that moves axially is positioned to around described axle sleeve, one of described second auxiliary sealing device provides described the move axially periphery of seal ring and the sealing between the described axle sleeve, and allowing the described seal ring that moves axially to move axially simultaneously with respect to described axle sleeve, described seal arrangement comprises that the auxiliary seal wall of at least one circumferentially extending remains on the position with respect to described axle sleeve axial restraint.

13. the encapsulating method that the process fluid that prevents to be in the axle box under the pressure leaks along passing the running shaft of axle box wall is characterized in that this method comprises:

One first rotating machinery end face seal body is provided, it comprises that one is used to seal with the fixing seal ring of axle box junction and one and is used to seal rotary seal ring with the axle junction, one of above-mentioned two seal rings can move axially with respect to the axle or the axle box that link with it, described each seal ring all has the corresponding sealing surface of the sealing surface that is generally circumferentially extending of an annular and described another seal ring to be to relatively rotate, the sealing relationship that cooperatively interacts, so that between them, form a seal interface, each described seal ring has the rear surface that is generally circumferentially extending of annular, it is axially spaced apart with described circumferentially extending sealing surface, the described first rotating machinery end face seal body also comprise one for O RunddichtringO that described sealing relationship is provided between fixing seal ring and the axle box and one for the O RunddichtringO of described sealing relationship is provided between rotating seal ring and the axle, so that the described sealing relationship between them to be provided, the O RunddichtringO that described and described axle moveable sealing links mutually be placed in one with the adjoining of the circumferentially extending wall of one of described and axle box axial restraint;

In axle rotation, when occurring, operate the described first rotating machinery end face seal body, the basic thrust that acts on the described first rotating machinery end face seal body of eliminating as the described pressure of the described relative inertness gas of the non-contact sealing of gas lubrication;

The O RunddichtringO of the described first rotating machinery end face seal body defines the boundary between described intermediate cavity and the described axle box, thereby makes because hydrodynamic pressure will be described moves axially seal ring presses to the end thrust that described another seal ring produces and equal at least owing to hydrodynamic pressure described another seal ring to be pressed to the described end thrust that seal ring produces that moves axially;

On the sagittal plane of one of described seal ring of the described first rotating machinery end face seal body, be provided with a plurality of spiral chutes, the described circumference of their relative inertness gas from be exposed to described intermediate cavity extends towards the described circumferential section of the process fluid that is exposed to described axle box inside, on described, form one near the ring dam that is exposed to the described circumference of described process fluid in the described axle box, thereby make described relative inertness gas from of described the relatively rotating of described intermediate cavity by the described first rotating machinery end face seal body, the sealing surface that cooperatively interacts is pumped to described axle box.